Thread: 305 pushin 480HP?

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Originally Posted by tony evans

hi just a slight side track but tech you have some figures for a 350 producing 500 horses and you suggest a stall of 2800 whan i look at the figs i see it makes 375 ilbs of torque at 2000 surely thats enough to launch quickly if you have a 2000 stall and wouldnt it make for a more street freindly ride? im not saying im right i just looked at the figs and put them in a drag race simulator and changing thew stall to 2000 made less than a tenth difference,surely undetectable in evryday street driving?
the reason im asking is i have a set up that will make good torque at 2000 but the cam card suggests a 3000 stall ??????

Yeah Tony, the way I see it, the cam companies list the stall on the short side of the 3500 rpm range of the cam. That keeps them out of trouble. Most guys will overcam the motor in relation to the static compression ratio and the motor will not generate the torque the owner thinks it should based on the cam specs and may not stall to the point he thinks it should. So, if the cam company fudges a little, they have a cushion. They are in business to generate repeat customers, not dis-satisfied customers. In my opinion, this is purely a judgement call by the car owner. If you think the motor will be generating enough torque to demonstrate good acceleration with a shorter converter, then by all means go for it. A 2000 stall converter may stall at 1500 in one motor and 2500 in another motor. It just depends on the torque generated by the motor at that particular rpm.

Everyone else reading this needs to understand that any cam you bolt into the motor will have an effective operating range of about 3500 rpm's. It might make power from idle to 4000 or from 1500 to 5000 or from 2500 to 6000 or from 5000 to 8500, depending on the valve opening and closing events that are ground onto the cam lobes when the cam is manufactured. If, for instance, you built the motor with high-buck parts with a target rpm limit of 8500, the cam would be ground to generate power from 5000 to 8500. Under 5000, it wouldn't pull the hat off your head (an exaggeration to make a point), so you'd want to bolt a converter onto the crank (5000 stall for instance) that would allow the motor to rev past the dead zone and get up into the power range of the cam. Most every hot rodder will agree that a 3000 stall converter is about all you want to try to live with on the street, so at a max, you might want to build the motor to make power from 3000 to 6500 on a street motor and 2000 to 5500 would be way more manageable and more fun to drive. We had a saying in the Navy.... "theres always that 1 percent"....., meaning that there will always be 1 percent of the people out there who will try to run a 5000 stall converter on the street.